Abstract: Wireless sensor network technology provides a new measure for moisture information collection in large-scale paddyfield. In this study, the key technology of constructing the paddy moisture sensor network (PMSN) was investigated based on the wireless moisture-content and water-layer sensor (WFDMS). Several key technical issues in building PMSN were solved and a large-scale remote topology management program was constructed. A low power loss transfer protocol for PMSN (LPTP-PMSN) was proposed. Finally, a network information management system was developed to monitor and analyze the moisture information. Experiments results showed that the reliable communication range among the senor nodes was up to 60 m. Supported by the 3.6-volt 2100 mAh batteries, under the control of the transfer protocol LPTP-PMSN, the sensors, cluster head, base stations, SMS gateway and computer worked collaboratively and the whole paddy moisture sensor networks could work together reliably. The node lifetime can be over 190 d under the sampling intervals of 4 h. This research can provide a reference for monitoring other fields sensitive information based on wireless transmission networks.